Estancia San Miguel SM10' (Cretaceous of Argentina)

Also known as Telsen, La Colonia

Where: Chubut, Argentina (42.5° S, 66.8° W: paleocoordinates 44.9° S, 55.2° W)

• coordinate estimated from map

When: La Colonia Formation, Maastrichtian (72.1 - 66.0 Ma)

Environment/lithology: coastal; mudstone

• Two well-defined intervals characterize an intertidal-flat zone interpreted for the middle part of the San Miguel section; the lower one, associated with a cyclic coarsening upward pattern –mudstones to fine sandstones– represented by heterolithic facies (flaser, lenticular and wavy lamination) would correspond to a mixed flat (Fig. 2). In turn, the upper interval exhibits banded muddy rhythmites and laminated mudstones, represented by fine heterolithic facies, bioturbated, related to a mud flat (Fig. 2). Toward the uppermost part of the section, the deposits consist of facies with a very fine massive texture –predominantly claystones– probably originated by decantation processes in the water column linked to a supratidal environment
• laminated mudstone

Size class: microfossils

Preservation: trace

Collection methods: chemical, sieve,

• Samples were taken at regular stratigraphic intervals of 20–30 cm from the base to the top of the San Miguel section, where the La Colonia Formation is exposed. The chemical (palynological) processing of the samples included HCl and HF- removal of carbonates and silicates. Organic residues were sieved at 10 and 20 μm, stained with Bismarck C and mounted in glycerin jelly.

Primary reference: M. V. Guler, C. M. Borel, H. Brinkhuis, E. Navarro, and R. Astini. 2014. Brackish to freshwater dinoflagellate cyst assemblages from the La Colonia Formation (Paleocene?), northeastern Patagonia, Argentina. Ameghiniana 51(2):141-153 [E. Vlachos/E. Vlachos]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 229244: authorized by Evangelos Vlachos, entered by Evangelos Vlachos on 24.02.2023

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Equisetopsida
 Pinidae - Pinidae
Classopollis sp.
Classopollis sp. Pflug 1953
Algae
  -
Algae indet.
  - Zygnemataceae
Ovoidites sp.
Ovoidites sp. Krutzsch 1959
  - Botryococcaceae
Botryococcus sp.
Botryococcus sp. Kutzing 1849
Chlorophyceae
  -
Pediastrum sp.
Pediastrum sp. Meyen 1829
Schizosporis reticulatus
  -
Schizosporis reticulatus
Schizosporis reticulatus Cookson and Dettmann 1959